Rolling mill



June 28, 1938;

H,PUPPE ROLLING MILL Filed July a1, 1937 I REL,

2 Sheets-Sheet 1 June 28, 1938. H, PUPPE 2,121,929

ROLLING MILL Filed July 31, 1937 2 Sheets-sheet 2 1:1 I ,7 g a: E2 j I H: r i I 59.8 U Hid J'wmfon Patented June 28 1938 PATENT OFFICE ROLLING MILL Heinz Puppc, Neunkirchen, Germany Application July 31, 1937, Serial No. 156,779

' In Germany March 4, 1936 4 Claims. (01. 80-35) This invention relates to a rolling mill with roll stands arranged in series for the continuous hot rolling of strip iron or broad band iron, more particularly strip or band iron having a breadth greater than 600 millimetres. Experience has shown that in-these cases a profiling of the rolls such as is known in the manufacture of individual sheets or of individual 7 piles or fagots, wherein the roll openings of the i0 successive roll stands are convex in shape, so that each roll opening is less convex than the roll opening of the preceding roll stand, is unsatisfactory, because vthe final products are not dimensioned correctly enough, the thickness of the broad band iron producedfluctuates considerably, the condition of the edges leaves a good deal to be desired, and finally the continuous removal of scale between one roll stand and the next is hardly practicable.

In particular the obtaining or producing of a satisfactory surface in rolling strip iron of a breadth exceeding 600 millimetres presents very great difllculties, because the scale that forms on the surface of the strip pan hardly be removed 2 in the short space between the successive roll stands, in

- that it is rolled into the surface of the band,

thereby leading to defective surfaces and even to' a useless product.

Now according tothe present invention, these disadvantages are obviated by constructing the rollopenings in the individual roll stands convex and concave, and by reversing this construction between successive roll stands, the magnitude of 35 the convexity or concavity, or in other words the angle that determines the magnitude of the convexity or concavity, preferably varying in such a way that the roll opening has its thickness in the centre.

That the roll openings become progressively flatter will be self-evident. I The roll stands may be equipped, as multi-roll stands, with rolls of different diameters. This succession of stands may then be followed in a known manner by multi-roll stands with straight rolls, the working rolls of which are of smaller diameter than the other rolls.

One embodiment of th invention is illustrated 50 by way of example in the accompanying drawings, in which .Figure 1 shows the rolling mill diagrammatically in side elevation; 3

Figure 2 shows a sec ion on the line 2-2 in as W view of the breadth of the band, so

provided rollers 5.

. ticular Figure 5 shows on the upper side and convex Figure 3 is a front view of any one of the alternate roll stands I, III or V;

Figure 4 is a front view of any one of the roll stands II or IV;

Figure 5 shows in cross section the shape of the roll opening in one group of stands, this roll opening being concave on the upper side and convex on theunder side;

Figure 6 is a similar view of the roll opening of the intervening stands which is convex on the upper side and concave on the under side;

Figure 7 is a view similar to Figure 5, but showing a narrower roll opening occurring at a later stage in the series of roll stands, and

Figure8 is a similar view of the finishing roll opening.

As will be gathered from Figure 1 the workpiece Benters the rolling plant from the' left and travels through the individual roll stands I to V, which are constructed as multiple roll stands, each with two inner working rolls i, 2 or I, 2 of relatively small diameter, and two outer supporting rolls 3, 4 or 3', 4' of larger diameter. In

other respects the construction of these roll stands, which are equipped with the usual-driving and adjusting means, is known.

As shown in Figures 3 and 4 the rolls I and 2 are concave, and the rolls l' and 2 are convex. The roll openings in the stands I, III and V are therefore convex as viewed from above and concave as viewed from below, whereas the roll openings of the stands II and IV are concave as viewed from above and convex as viewed from below.

Before, between and behind the roll stands are As Figure 1 shows, the work may be given a looped-form if this should be desirable.

Figures 5 to 8 show on a larger scale the shape of the roll opening at 4 successive stages. In parthe workpiece Ga concave on .the under side, as shaped by a convex upper roll and a concave lower roll, like those of the stands II and IV.

Figure 6 hows the workpiece 8b with a convex upper surface and a concave under surface, as produced by a roll stand with a concave upper roll and a convex lower roll, as in the case of the roll stands I, III and V.

Figure 7 shows the workpiece 60 with a cross section similar to that of Figure 5, except that it has been reduced in thickness in its progress through the rolling mill.

Finally Figure v8 shows the cross section of the finished strip id.

The rolling operation proceeds as follows: When the metal enters the first roll stand, which may be equipped for example with a concave upper roll and a convex lower roll, the work receives a cross section which is convex on the upper side and concave on the lower side. Since in the next roll stand there is a convex upper roll and a concave lower roll, the work receives a cross section with a concave upper side and a convex under side. In succeeding roll stands there is again a concave upper roll and a convex lower roll, so that the work receives a cross section with a convex upper side and a concave under side.

This cycle of operations described above is repeated.

What I claim is:-

1. A rolling mill with roll stands arranged in series for the continuous hot rolling of strips and broad long bands of iron of a breadth greater than 600 millimetres, comprising roll stands arranged one behind each other, bottom working rolls and top working rolls mounted in said roll stands, the arrangement being such that the bottom working rolls of successivepasses are alternately concave and convex, whereas the said top working rolls are alternately convex and concave.

2. A rolling mill with roll stands arranged in series for the continuous hot rolling of strips and broad long bands of iron of a breadth greater than 600 millimetres, comprising roll stands arranged one behind each other, bottom working rolls and top working rolls mounted in said roll stands, the arrangement being such that the bottom working rolls of successive passes are alternately concave and convex, whereas the said top working rolls are alternately convex and concave, and the curvature of the concave side of a roll opening differing from the curvature of the convex side of the same roll opening.

3. A rolling mill with roll stands arranged series for the continuous hot rolling of strips and broad long bands of iron of a breadth greater than 600 millimetres, comprising roll stands arranged one behind each other, bottom working rolls and top working rolls mounted in said roll stands, the arrangement being such that the bottom working rolls of successive passes are alternately concave and convex, whereas the said top working rolls are alternately convex and concave, and each roll stand including supporting rolls in addition to working rolls.

4. A rolling mill with roll stands arranged in series for the continuous hot rolling of strips and broad long bands of iron of a breadth greater than 600 millimetres, comprising roll stands arranged one behind each other, bottom working rolls and top working rolls mounted in said roll stands, the arrangement being such that the bottom working rolls of successive passes are alternately concave and convex, whereas the said top working rolls are alternately convex and concave, the roll opening between the working rolls of at least one roll stand at the end of the series being straight, and the finishing working rolls being of smaller diameter than the preceding rolls and each roll stand including at least two supporting rolls in addition to the working rolls.- v

HEINZ PUPPE. 

